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The Pregnancy Week to Month Converter is a free, private tool that runs entirely in your browser — your inputs never leave your device, and the answer appears the instant you enter them.

Pregnancy brings a calendar full of dates and milestones — due date, trimester boundaries, and the weeks between scans. This Pregnancy Week to Month Converter computes one of those key dates from the information you have, so you can plan appointments and preparations.

The due date is most commonly estimated as 40 weeks from the first day of the last menstrual period (LMP) — the standard Naegele's rule used by obstetricians. If you know your conception date or current week instead, the tool works from what you have.

Only about 5% of babies arrive exactly on the due date; it is an estimate around week 40 that your doctor refines with ultrasound measurements. Treat the result as the planning date, not a promise.

Use the result to schedule the key scans — the first-trimester dating scan, the anomaly scan around 18–22 weeks, and the glucose test in the third trimester — and to plan maternity leave and the nursery.

Come back to the Pregnancy Week to Month Converter whenever your numbers change; because everything runs live in your browser, you can re-run it as many times as you need at no cost.

Numbers should not slow you down. The Conception Date Calculator does the arithmetic for you and shows the result live, so you can focus on the decision rather than the maths.

Pregnancy brings a calendar full of dates and milestones — due date, trimester boundaries, and the weeks between scans. This Conception Date Calculator computes one of those key dates from the information you have, so you can plan appointments and preparations.

The due date is most commonly estimated as 40 weeks from the first day of the last menstrual period (LMP) — the standard Naegele's rule used by obstetricians. If you know your conception date or current week instead, the tool works from what you have.

Only about 5% of babies arrive exactly on the due date; it is an estimate around week 40 that your doctor refines with ultrasound measurements. Treat the result as the planning date, not a promise.

Use the result to schedule the key scans — the first-trimester dating scan, the anomaly scan around 18–22 weeks, and the glucose test in the third trimester — and to plan maternity leave and the nursery.

For the most accurate outcome from the Conception Date Calculator, keep the editable rates and defaults up to date with current figures before reading the result.